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Running an LED Test

Hello everyone,

After combing through a few mountains of data/posts and watching an absurd amount of video, I am still unclear on which LED to use for my grow.

So I decided to run a test! Good old fashioned side by side(x5). Currently looking at running these lights:

NextLight Mega

Gavita LED

HLG 550 V2

Optic 8+

2 x ES 300s

Heliospectra LX601C

Along with a 1000W HPS as a “Control.”

All will be in their own 4x4 Tents, growing identical genetics in identical conditions. close to as possible

I am really looking to compare the yield and terpene production, so I will have each result tested by a lab as if it was going onto the shelf.

Efficiency is also key to large scale commercial production so every tent will be monitored for electrical consumption, this will be a lesser factor in my test simply because the room the tents will be in is climate controlled so HVAC costs cannot be factored in as well.

Purpose of the post is to ask for input! Anything and everything you can think of I may be missing or something I could easily add.


You should share your results on the community so we can all learn from your research.


Bookmarked and following. Good luck!


That’s the plan! Video documented the whole way, shared for the world to see.


you ever thought of building your own cobs ? otherwise known as Chip On Board go to youtube and search for Deadmau5 all you ever will need to know this guy can show you , he even has his own chips now …


Have you considered testing a light capable of delivering blue rich finishing spectrum at the end of flower?


@GrowFlux I definitely have, that’s why I included the Heliospectra. Light spectrum control is a huge plus for me, because that is where the future is in my opinion.

@medicinemangenetics Honestly don’t trust myself to put together 60-70 lights and bank my entire operation on them, I call myself many things an engineer is not one!


Firstly, thank-you! This is a fantastic experimental opportunity.

Input? I have some :slight_smile: I would suggest each light be tested on a good photometric uniformity mat, with a quantum sensor. This will help you generate a PAR map for each, and observe the variance amongst each array’s PAR spikes. With proper dimming systems now in operation, the goal is to achieve uniformity. Once proper uniformity has been achieved, its simply a matter of turning a knob, or pressing a button, or maybe even via a slider on your cell phone. Don’t worry about directly comparing the, ‘PPFD scores’ - or, the ‘average’ of single-spot measurements, with no mathematical relation accounted for in the equation. Observing the PAR maps/results from your grows is good enough for now. It appears new math is required to properly quantify/prove true photosynthetic photon flux density, amongst other relevant things, and we are currently in the process of developing that.

You can use ours:

The file sized/formatted for printing is too large to be posted here. We could send it if you want though.

If you have a spectrometer, the data produced by that would be useful to report. I wouldn’t go buy one just for this, though. However, you are interested in tunability of spectrum, etc. - So I doubt you’d feel its a wasteful purchase. One could use the reports, coupled with the results and visual representations produced through your experiments, to observe differences in photochemical efficiency, based on differential within the plants’ absorption of the different spectra produced by the arrays being tested.

We are very interested in learning more about how these plants respond to different spectra. We’re tuned in. Thanks again.


Take a look at a post I did today on old technique new use in Cannabis.

This will give you a way to measure what the plants are actually going to use and what the are going to reflect

I use the old spinach experiment fro basic biology. Which would be something you can refine the methodology.


Any updates here?


Yes sir, just accumulating everything I need. I have updated the light list, to include a couple options.

The test will be:

2x ES 300s
FluxScale Top Light
HLG 550v2
Optic 8+
Gavita Hortistar 1000 DE HPS
Nanolux CMH 1000w


What bulb will you be running in that HPS? Is it brand new? This is an important detail as there are a lot of 1000w lamps on the market and they are NOT all created equal! Also, they lose a lot of their luminosity over time. I recommend using them for flower for 9 months then using for a cycle or two of veg then tossing them out because they have lost so much brightness. I have a hard time with the waste generated by these old lights. They work well, they’re just wasteful!

I think you’ll enjoy the FluxScale’s overall ability to program down to the exact watt in the color spectrum you want. These are powerful tools we growers now have to work with!


Nether are Metal archec haloids

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Should have been more specific, using the Gavita Hortistar 1000 DE. Will also use a MH bulb (SolisTek 1000 DE) for veg.


Cool! Good to know. Thanks for keeping us informed and looking forward to the test and results!


I remember there bulbs as being fragile. They have to of made improvements scene the late time I bought one.

Five dollars on the @GrowFlux to win!


what were the results?